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Integration help

  1. Dec 17, 2006 #1
    How to integrate: x / (1+x)
  2. jcsd
  3. Dec 17, 2006 #2


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    "By parts" would be my first stab at it
  4. Dec 17, 2006 #3
    Would integrating, [tex] \frac{1}{1+x} [/tex] be any easier?

    If you got rid of the [itex] x [/itex] on the top it might make your life easier right?

    [tex] \frac{x}{1+x} [/tex]

    [tex] \frac{x}{1+x} - \frac{1+x}{1+x} = \frac{-1}{1+x} [/tex]

    [tex] \frac{x}{1+x}=\frac{-1}{1+x}+\frac{1+x}{1+x} [/tex]

    [tex] \frac{x}{1+x} = \frac{1+x}{1+x} - \frac{1}{1+x} [/tex]

    [tex] \frac{x}{1+x} = 1 - \frac{1}{1+x} [/tex]

    Obviously you don't have to do that in as many steps.
  5. Dec 17, 2006 #4


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    Use the substitution 1 + x = t.
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